[IAST] Move analyzers init to an explicit call

[daniel-romano-DD]

Summary of changes

Make IAST analyzers initialization explicit, and call it only in Instrumentation.Initialize to avoid multiple instances scenarios

Reason for change

A crash under these circumstances has been detected

Implementation details

Move IAST analyzers init inside Instrumentation.Initialize only to make sure they are initialized only once

Test coverage

Other details

[datadog-ddstaging]

Datadog Report

Branch report: dani/iast/hardcodedsecrets_init_fix
Commit report: 59fb803
Test service: dd-trace-dotnet

✅ 0 Failed, 344564 Passed, 1780 Skipped, 15h 7m 14.82s Total Time

[andrewlock]

Execution-Time Benchmarks Report ⏱️

Execution-time results for samples comparing the following branches/commits:

• This PR (5920)
• master

Execution-time benchmarks measure the whole time it takes to execute a program. And are intended to measure the one-off costs. Cases where the execution time results for the PR are worse than latest master results are shown in red. The following thresholds were used for comparing the execution times:

• Welch test with statistical test for significance of 5%
• Only results indicating a difference greater than 5% and 5 ms are considered.

Note that these results are based on a single point-in-time result for each branch. For full results, see the dashboard.

Graphs show the p99 interval based on the mean and StdDev of the test run, as well as the mean value of the run (shown as a diamond below the graph).

[andrewlock]

Benchmarks Report for appsec 🐌

Benchmarks for #5920 compared to master:

• 3 benchmarks are faster, with geometric mean 1.174
• 1 benchmarks are slower, with geometric mean 1.134
• All benchmarks have the same allocations

The following thresholds were used for comparing the benchmark speeds:

• Mann–Whitney U test with statistical test for significance of 5%
• Only results indicating a difference greater than 10% and 0.3 ns are considered.

Allocation changes below 0.5% are ignored.

Benchmark details

Benchmarks.Trace.Asm.AppSecBodyBenchmark - Slower ⚠️ Same allocations ✔️

Slower ⚠️ in #5920

Benchmark	diff/base	Base Median (ns)	Diff Median (ns)	Modality
Benchmarks.Trace.Asm.AppSecBodyBenchmark.ObjectExtractorSimpleBody‑netcoreapp3.1	1.134	210.62	238.88

Faster 🎉 in #5920

Benchmark	base/diff	Base Median (ns)	Diff Median (ns)	Modality
Benchmarks.Trace.Asm.AppSecBodyBenchmark.ObjectExtractorMoreComplexBody‑net472	1.172	4,439.31	3,788.06
Benchmarks.Trace.Asm.AppSecBodyBenchmark.ObjectExtractorSimpleBody‑net472	1.157	196.29	169.61

Raw results

Branch	Method	Toolchain	Mean	StdError	StdDev	Gen 0	Gen 1	Gen 2	Allocated
master	AllCycleSimpleBody	net6.0	74.3μs	109ns	422ns	0.0749	0	0	6 KB
master	AllCycleSimpleBody	netcoreapp3.1	62μs	76.1ns	295ns	0.0939	0	0	6.95 KB
master	AllCycleSimpleBody	net472	49.4μs	55.2ns	214ns	1.31	0	0	8.34 KB
master	AllCycleMoreComplexBody	net6.0	78.8μs	76.9ns	298ns	0.118	0	0	9.51 KB
master	AllCycleMoreComplexBody	netcoreapp3.1	69.2μs	67ns	260ns	0.138	0	0	10.36 KB
master	AllCycleMoreComplexBody	net472	55.9μs	65.8ns	246ns	1.87	0.0279	0	11.85 KB
master	ObjectExtractorSimpleBody	net6.0	140ns	0.117ns	0.452ns	0.00397	0	0	280 B
master	ObjectExtractorSimpleBody	netcoreapp3.1	210ns	0.136ns	0.526ns	0.0037	0	0	272 B
master	ObjectExtractorSimpleBody	net472	196ns	0.132ns	0.511ns	0.0446	0	0	281 B
master	ObjectExtractorMoreComplexBody	net6.0	3.06μs	1.67ns	6.24ns	0.0535	0	0	3.78 KB
master	ObjectExtractorMoreComplexBody	netcoreapp3.1	3.96μs	1.82ns	7.04ns	0.0495	0	0	3.69 KB
master	ObjectExtractorMoreComplexBody	net472	4.44μs	2.34ns	8.75ns	0.602	0.00666	0	3.8 KB
#5920	AllCycleSimpleBody	net6.0	72.7μs	79.9ns	299ns	0.0731	0	0	6.01 KB
#5920	AllCycleSimpleBody	netcoreapp3.1	62.2μs	81.9ns	306ns	0.0929	0	0	6.95 KB
#5920	AllCycleSimpleBody	net472	49μs	52.6ns	189ns	1.3	0	0	8.34 KB
#5920	AllCycleMoreComplexBody	net6.0	78.8μs	79.4ns	297ns	0.121	0	0	9.51 KB
#5920	AllCycleMoreComplexBody	netcoreapp3.1	70.5μs	89.6ns	347ns	0.105	0	0	10.36 KB
#5920	AllCycleMoreComplexBody	net472	55.8μs	43.2ns	167ns	1.86	0.0282	0	11.85 KB
#5920	ObjectExtractorSimpleBody	net6.0	142ns	0.188ns	0.702ns	0.00394	0	0	280 B
#5920	ObjectExtractorSimpleBody	netcoreapp3.1	239ns	0.163ns	0.586ns	0.00373	0	0	272 B
#5920	ObjectExtractorSimpleBody	net472	169ns	0.34ns	1.32ns	0.0446	0	0	281 B
#5920	ObjectExtractorMoreComplexBody	net6.0	3.04μs	2.12ns	7.94ns	0.054	0	0	3.78 KB
#5920	ObjectExtractorMoreComplexBody	netcoreapp3.1	3.84μs	2.73ns	10.6ns	0.0499	0	0	3.69 KB
#5920	ObjectExtractorMoreComplexBody	net472	3.79μs	2.58ns	9.64ns	0.603	0.00569	0	3.8 KB

Benchmarks.Trace.Asm.AppSecEncoderBenchmark - Same speed ✔️ Same allocations ✔️

Raw results

Branch	Method	Toolchain	Mean	StdError	StdDev	Gen 0	Gen 1	Gen 2	Allocated
master	EncodeArgs	net6.0	38.1μs	22.9ns	88.8ns	0.454	0	0	32.4 KB
master	EncodeArgs	netcoreapp3.1	54.7μs	31.7ns	123ns	0.433	0	0	32.4 KB
master	EncodeArgs	net472	65.9μs	29.5ns	114ns	5.15	0.0664	0	32.5 KB
master	EncodeLegacyArgs	net6.0	80.5μs	172ns	667ns	0.0399	0	0	2.14 KB
master	EncodeLegacyArgs	netcoreapp3.1	108μs	109ns	420ns	0	0	0	2.14 KB
master	EncodeLegacyArgs	net472	151μs	33.6ns	126ns	0.302	0	0	2.15 KB
#5920	EncodeArgs	net6.0	37.9μs	18ns	69.7ns	0.456	0	0	32.4 KB
#5920	EncodeArgs	netcoreapp3.1	54.9μs	15.1ns	54.4ns	0.438	0	0	32.4 KB
#5920	EncodeArgs	net472	66.7μs	42.3ns	164ns	5.16	0.0666	0	32.5 KB
#5920	EncodeLegacyArgs	net6.0	77.2μs	422ns	2.43μs	0	0	0	2.14 KB
#5920	EncodeLegacyArgs	netcoreapp3.1	105μs	254ns	982ns	0	0	0	2.15 KB
#5920	EncodeLegacyArgs	net472	152μs	54ns	209ns	0.305	0	0	2.15 KB

Benchmarks.Trace.Asm.AppSecWafBenchmark - Same speed ✔️ Same allocations ✔️

Raw results

Branch	Method	Toolchain	Mean	StdError	StdDev	Gen 0	Gen 1	Gen 2	Allocated
master	RunWafRealisticBenchmark	net6.0	188μs	67.1ns	251ns	0	0	0	2.42 KB
master	RunWafRealisticBenchmark	netcoreapp3.1	197μs	124ns	447ns	0	0	0	2.37 KB
master	RunWafRealisticBenchmark	net472	211μs	49.4ns	178ns	0.316	0	0	2.43 KB
master	RunWafRealisticBenchmarkWithAttack	net6.0	122μs	105ns	407ns	0	0	0	1.46 KB
master	RunWafRealisticBenchmarkWithAttack	netcoreapp3.1	131μs	70ns	271ns	0	0	0	1.45 KB
master	RunWafRealisticBenchmarkWithAttack	net472	140μs	38.4ns	144ns	0.21	0	0	1.48 KB
#5920	RunWafRealisticBenchmark	net6.0	185μs	32.2ns	120ns	0	0	0	2.42 KB
#5920	RunWafRealisticBenchmark	netcoreapp3.1	196μs	110ns	426ns	0	0	0	2.37 KB
#5920	RunWafRealisticBenchmark	net472	209μs	51.8ns	194ns	0.314	0	0	2.43 KB
#5920	RunWafRealisticBenchmarkWithAttack	net6.0	122μs	83.6ns	324ns	0	0	0	1.46 KB
#5920	RunWafRealisticBenchmarkWithAttack	netcoreapp3.1	130μs	52.5ns	189ns	0	0	0	1.45 KB
#5920	RunWafRealisticBenchmarkWithAttack	net472	139μs	45.7ns	171ns	0.209	0	0	1.48 KB

Benchmarks.Trace.Iast.StringAspectsBenchmark - Faster 🎉 Same allocations ✔️

Faster 🎉 in #5920

Benchmark	base/diff	Base Median (ns)	Diff Median (ns)	Modality
Benchmarks.Trace.Iast.StringAspectsBenchmark.StringConcatBenchmark‑netcoreapp3.1	1.192	63,200.00	53,000.00	bimodal

Raw results

Branch	Method	Toolchain	Mean	StdError	StdDev	Gen 0	Gen 1	Gen 2	Allocated
master	StringConcatBenchmark	net6.0	59.9μs	752ns	7.44μs	0	0	0	43.44 KB
master	StringConcatBenchmark	netcoreapp3.1	64.1μs	911ns	8.93μs	0	0	0	42.64 KB
master	StringConcatBenchmark	net472	37μs	120ns	432ns	0	0	0	59.04 KB
master	StringConcatAspectBenchmark	net6.0	319μs	1.76μs	11.2μs	0	0	0	264.42 KB
master	StringConcatAspectBenchmark	netcoreapp3.1	336μs	1.21μs	4.37μs	0	0	0	255.34 KB
master	StringConcatAspectBenchmark	net472	277μs	5.54μs	54μs	0	0	0	278.53 KB
#5920	StringConcatBenchmark	net6.0	61.1μs	730ns	7.23μs	0	0	0	43.44 KB
#5920	StringConcatBenchmark	netcoreapp3.1	53.1μs	293ns	1.73μs	0	0	0	42.64 KB
#5920	StringConcatBenchmark	net472	37μs	85.8ns	321ns	0	0	0	59.04 KB
#5920	StringConcatAspectBenchmark	net6.0	305μs	1.6μs	10.8μs	0	0	0	264.1 KB
#5920	StringConcatAspectBenchmark	netcoreapp3.1	336μs	1.76μs	12.7μs	0	0	0	254.33 KB
#5920	StringConcatAspectBenchmark	net472	292μs	5.62μs	54.8μs	0	0	0	278.53 KB