Split client into multiple files and add more tests (woodpecker-ci#3647)

All the client functions were in a single file, which was already very
long, and the test file gets even longer as more tests are added. I
split it into separate files representing the API path and started
adding some tests.

.gitignore

@@ -13,7 +13,7 @@
 *.so
 *.dylib
 vendor/
-__debug_bin
+__debug_bin*
 
 # Test binary, built with `go test -c`
 *.test

woodpecker-go/woodpecker/agent.go

@@ -0,0 +1,50 @@
+package woodpecker
+
+import "fmt"
+
+const (
+	pathAgents     = "%s/api/agents"
+	pathAgent      = "%s/api/agents/%d"
+	pathAgentTasks = "%s/api/agents/%d/tasks"
+)
+
+// AgentCreate creates a new agent.
+func (c *client) AgentCreate(in *Agent) (*Agent, error) {
+	out := new(Agent)
+	uri := fmt.Sprintf(pathAgents, c.addr)
+	return out, c.post(uri, in, out)
+}
+
+// AgentList returns a list of all registered agents.
+func (c *client) AgentList() ([]*Agent, error) {
+	out := make([]*Agent, 0, 5)
+	uri := fmt.Sprintf(pathAgents, c.addr)
+	return out, c.get(uri, &out)
+}
+
+// Agent returns an agent by id.
+func (c *client) Agent(agentID int64) (*Agent, error) {
+	out := new(Agent)
+	uri := fmt.Sprintf(pathAgent, c.addr, agentID)
+	return out, c.get(uri, out)
+}
+
+// AgentUpdate updates the agent with the provided Agent struct.
+func (c *client) AgentUpdate(in *Agent) (*Agent, error) {
+	out := new(Agent)
+	uri := fmt.Sprintf(pathAgent, c.addr, in.ID)
+	return out, c.patch(uri, in, out)
+}
+
+// AgentDelete deletes the agent with the given id.
+func (c *client) AgentDelete(agentID int64) error {
+	uri := fmt.Sprintf(pathAgent, c.addr, agentID)
+	return c.delete(uri)
+}
+
+// AgentTasksList returns a list of all tasks for the agent with the given id.
+func (c *client) AgentTasksList(agentID int64) ([]*Task, error) {
+	out := make([]*Task, 0, 5)
+	uri := fmt.Sprintf(pathAgentTasks, c.addr, agentID)
+	return out, c.get(uri, &out)
+}